The author of this volume has a special ability in making clear to any fairly intelligent reader the biologic processes associated with reproduction both in man and in animals. The publisher has done well in printing a book that is easily readable and artistic. The book is divided into six parts covering the basic biologic factors, sex rhythms, disturbances of the male and female development, determination of sex, sterility and fertility, and multiple births. The volume is enlivened with numerous quotations from literature, with epigrams and with case reports. It should be read with great interest not only by the public but also by physicians, who are frequently asked questions which this book answers.